diff --git a/scripts/install b/scripts/install
index 587affb..2ae1d22 100644
--- a/scripts/install
+++ b/scripts/install
@@ -57,9 +57,8 @@ pushd $install_dir
 	fi
 	[[ -v HOME ]] && TMP_HOME=$HOME
 	HOME=$(pwd)
-	export NODE_ENV=production
 	ynh_use_nodejs
-	ynh_npm install --ignore-scripts
+	ynh_exec_warn_less sudo -u $app env $ynh_node_load_PATH NODE_ENV=production $ynh_npm install --ignore-scripts
 	[[ -v TMP_HOME ]] && HOME=$TMP_HOME || unset HOME
 popd
 
diff --git a/scripts/upgrade b/scripts/upgrade
index a34184b..4f5b0dc 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -69,7 +69,7 @@ pushd $install_dir
 	[[ -v HOME ]] && TMP_HOME=$HOME
         HOME=$(pwd)
         ynh_use_nodejs
-        ynh_npm update
+        ynh_exec_warn_less sudo -u $app env $ynh_node_load_PATH NODE_ENV=production $ynh_npm install --ignore-scripts
         [[ -v TMP_HOME ]] && HOME=$TMP_HOME || unset HOME
 popd